Blue tetrakisazo dyes for cotton and process of making same



Patented May 14, 1929.

UNITED STATES PATENT OFFICE.

HENRY JORDAN, OF WILMINGTON,

DELAWARE, ASSIGNOR TO E. I. DU PONT DE NEMOURS & COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELA- WARE.

BLUE TETRAKISAZO DYES FOR COTTON AND PROCESS OF MAKING SAME.

No Drawing.

This invention relates to blue tetrakisazo dyes for cotton and the process for making same, which comprises forn'iing an intermediate by coupling a diazo compound of a mono-- acidyl-l:l-arylene-diamine with an arylamine not containing a free hydroxy group, diazotizing the intermediate, coupling the diazotized intermediate with Q-dinaphthylamine-5 5-dihydroxy-7 7 -disulphonic acid 0 and saponifying the product of the lastnamed coupling.

The first components used in the process are the mono-acidyl-l:L-arylene-diamines and their derivatives. Among the suitable compounds which may be used are, e. g., monoformyL, m0no-acetyl-, or mono-oxalyl-lz lphenylenediamine, 2-acetyl-amino- 5 aminoanisol, 2-oxalyl-amino-4-chlor-5 amino-anisol, 2-oxalyl-amino-4t-methyl-5 amino-anisol and their sulphonic acids, mono-acetyl-1:4:-

naphthalenediamine and its 6- or 7 -sulphonic acid.

As second components, comprising the amino compounds not containing a free hydroxy group, there niay be used, e. g., m-toluidine, p-

xylidine, cresidine, mono-acetyl-m-toluylenediamine, 4 acetyl 1 amino 2 amino-anisol, other amino-compounds of the benzene series suitable for another diazotization after hav- 3o ing been coupled, alpha-naphthylamine, al-

pha-naphthylamine 1: 6 or 1: 7 sulphonic acid, and alpha-naphthylamine-2-methoxy-6- sulphonic acid.

The dyes obtained by this process are, in their dry form, dark powders, dissolving in water with a reddish to greenish-blue coloration, dyeing cotton from reddish to greenishblue shades, which on diazotizing and developing on the fibre with beta-naphthol change only very little in color, but are remarkably increased in their fastness to washing. Those dyes having naphthalene derivatives as second components are superior, in their fastness to light, to the dyes having benzene deriva- Application filed September 19, 1925. Serial No. 57,467.

tives as second components. The dyes are also characterized by their exceptional brightness.

Example 1.

180 parts of mono-oxalyl-paraphenylenediamine are dissolved in a sodium carbonate 5 solution containing 53 parts of sodium carbonate in 4000 parts of Water. This solution is acidified with 280 parts of a 31% hydrochloric acid solution, and the acid mix is div azotized at 15 C. with a sodium nitrite solu- 55 tion containing 69 parts of sodium nitrite. 223 parts of l 6-Cleves acid is dissolved in a solution of 58 parts of sodium carbonate and 170 parts of sodium acetate in 4000 parts of water. To this last named solution is added 00 the diazo solution prepared as above. The coupling is complete in a few minutes- Theintermediate formed by the coupling is acidilied with 750 parts of a 31% hydrochloric acid solution and is then diazotized with a solution of 69 parts of sodium nitrite in water. This second diazotization iscomplete after one hours stirring at 1520 C. It is combined at 0-5 C. with a solution of 231 parts of 2-dinaphthylamine-5:5-dihydroxy-7 :7- 7 disulphonic acid in water containing 700 parts of sodium carbonate. After stirring five hours the coupled product is heated to 70 C. and salted out.. The unsaponified dye is soluble in water with a bright reddish-blue color, turning greener with acid. The paste stirred up with 3000 parts of water is heated up to boiling, then 150 parts of sodium hydroxide, used as a 30% solution, are added and the liquid is kept boiling for 30 minutes.

The saponified dye shows a greener shade than the unsaponified one, but turns redder with acid. By neutralizing the excess alkali with acid the dye is precipitated and can be filtered. Asa dry powder it has a bronzy appearance. It dissolves in water with a bri ht blue color. .It dyes cotton in bri ht b no shades, can be diazotized on the hrs and after developing with beta-naphthol shows a shade somewhat greener and brighter than the direct one, but of a very good fastness to washing and to light.

On reducing with stannous chloride this dye will give the following compounds: 2-dinaphthylamine 5:5 dihydroxy 6:6 diamino-7 :7 -disulphonie acid, 1 i-naphthylenediamine-6-sulph'onic acid, and paraphenylenediamine.

" E wample 2.

Instead of 180 parts of oxalyl-paraphenylenediarnineas in Example 1, 230 parts of lamino-benzene -4-acetyl amino -2- sulphonic acid are used as the first component, all other conditions being the same as in Example 1. The dye is even much greener and brighter than the one from the paraphenylenediamine, havinga still better fastness to light and, in spite of the additional sulpho group, the same good fastness to washing after develop- I ment with beta-naphthol.

On reducing with stannous chloride the dye will give the following compounds: 2-dinaphthylamine 5:5 dihydroxy 0 6 diamino-7 7'-disulphonic acid, 1 it-naphthylenediamine-G-sulphonic acid, and paraphenylenediamine sulphonic acid.

Emample 3.

naphthylamine 5 z 5' dihydroxy 6 :6 diamino-7:7-disulphonic acid and 4 moles of 1 :4-naphthalene-diamine-6-sulphonic acid.

Ewample 4.

230 parts of l-amino-benzene-4-acety1'- amino-Q-sulphonic acid are diazotized as in Example 2. There is added to the diazo compound a solution of 107 parts meta-toluidine in 1500 parts of water and 140 parts of a 31% hydrochloric acid. Coupling temperature is 15-20 C. The mineral acidity is neutralized with sodium acetate. The coupling will be complete after five to six hours stirring. After acidifying again with hydrochloric acid the intermediate dye is filtered. The paste is stirred up with 4000 parts of water and dissolved with caustic soda, containing parts of 100% sodium hydroxide. After cooling down to 10 C. the solution is acidified with 420 parts of hydrochloric acid. and diazotized at 1520 C. with 09 parts of sodium nitrite. After about one hours stirring the diazotization is complete. It is combined at 05 (J. with a solution of 231 parts of 2-dinaphthylaminc- 5 5-dihydroxy-7 7 -disulphonic acid in water containing 700 parts of sodium carbonate. The coupling shows a bluish-violet color. The dye is precipitated with salt and filtered. The paste-is saponified as shown in Example 1. The saponified dye shows a bluer shade than the unsaponificd one. It dyes cotton in bright bluish-violet shades, which on diazotizing and developing on the fibre with fl-naphthol turn into a bright reddish-blue of a very good fastness to washing.

On reducing with stannous chloride this dye will give the following products: .Z-dinaphthylan'iine 5 5 dihydroxy 6 6 dia1nino7 7'-disulphonic acid, paraphenylenediamine sulphonic acid, and 2:5-toluylenediamine.

By suitably varying the first, second or last components in the examples given, using suitable proportions, a large number of valuable blue tetrakisazo dyes for cotton may be prepared. Suitable changes may be made in the operating conditions without materially affecting the dyes obtained.

The following structural formulas are generaly indicative of the dyes formed in the various examples. The formula of the dye of Example. 1 obtained after development is also given for illustrative purposes.

Structural. formula of lfmumfle I lie/om development.

After development with beta-napkthol. Slmletwral formula of Example 4 before development.

SOaH N H- -S01H N- N 1% 0H 0H CHa CH N N SO|H $0.11

b1 133 NH| Structural fOWTI/Llblb of Example 92 before Structural formula of a dyestuff with oresidwezopment' dine before development. SOaH -NH- 0311 N N 80:11 NH BOIH l I OH on IIIII f N ll 0H 0H 0a11 soul -OGH| 011.0

b N CH1 CH] r SO3H SOaH N IL so H s l aH NH: N H, Structural formula of Example 3 before N'H: N a development.

soda --NH-- SO;H

N N It! I I clalm:

0 OH N 1. Blue tetrak1sazo dyes for cotton havmg the followlng structural formula: no

son; SOaH :1

H018 N som r m N I OH 0 1L soui- 80.11 E E N 3 El 1k! I l! in whichR represents an aryl group free having the following probable formula: 20 from hydroxy groups, and R represents an sour NH 0.11 aryl group conta1n1ng but one free amino group, said amino group being in the para. N N position, and said aryl group containing no ll 0 0 t other auxochrome group, said dyes being in their dry form dark powders, dissolving in water with a reddishto greenish-blue coloration, yielding on reduction withstannous chloride and hydrochloric acid, among other N N products, 2-dinaphthylamine-5 5-dihydrox- '3 J} 6 6'--diamino-7 7 -disulphonic acid, dyeing cotton reddishto greenish-blue shades, and Y .S0|H soar which dyes, when diazotized, and developed on the fibre with beta-naphthol, give bright 35 blue colors which are fast to washing and N N light. In testimony whereof I afiix my si ature. 2. A blue tetrakisazo dye for cotton HENRY JOB AN. 

